Carel pCO2 SMALL User manual

Brand: Carel

Model: pCO2 SMALL

Type: User manual

This manual is also suitable for

Application program for pCO¹ and pCO

Standard Shelter

Manual version 2.0 – April 01, 2003

Program code:

FLSTDMMSHE

We wish to save you time and money!

We can assure you that the thorough reading of this manual will guarantee correct installation and safe use of the product described.

IMPORTANT WARNINGS

BEFORE INSTALLING OR HANDLING THE DEVICE PLEASE CAREFULLY READ AND FOLLOW THE INSTRUCTIONS

DESCRIBED IN THIS MANUAL.

The equipment that this software has been designed for has been manufactured to operate risk-free for its specific purpose, as long

as:

• the installation, programming, operation and maintenance of the software are carried out according to the instructions contained in this

manual and by qualified personnel;

• all the required conditions described in the installation and operating manual for the equipment in question have been complied with.

All other uses and modifications that are not authorised by the manufacturer are considered incorrect.

Liability for injury or damage caused by incorrect use lies exclusively with the user.

INDEX

GENERAL............................................................................................................................................................................................................3

1.1

SHELTER........................................................................................................................................................................................................3

1.2

THE PROGRAM.............................................................................................................................................................................................3

1.3

SETTING UP THE pLAN NETWORK ..........................................................................................................................................................4

LIST OF CONFIGURATIONS.............................................................................................................................................................................5

2.1

DIGITAL INPUTS ..........................................................................................................................................................................................5

2.2

ANALOGUE INPUTS.....................................................................................................................................................................................5

2.3

DIGITAL OUTPUTS.......................................................................................................................................................................................5

2.4

ANALOGUE OUTPUTS.................................................................................................................................................................................5

TEMPERATURE CONTROL..............................................................................................................................................................................6

3.1

3.2

OTHER TEMPERATURE FUNCTIONS .......................................................................................................................................................7

3.3

HUMIDITY CONTROL..................................................................................................................................................................................7

3.4

OTHER HUMIDITY FUNCTIONS................................................................................................................................................................8

OUTLET LIMITATION.......................................................................................................................................................................................8

OUTLET FAN......................................................................................................................................................................................................9

CONDENSER FANS............................................................................................................................................................................................9

6.1

NUMBER OF PROBES AND CONDENSING COILS................................................................................................................................10

6.2

PREVENT FUNCTION.................................................................................................................................................................................10

6.3

SPEED-UP FUNCTION................................................................................................................................................................................10

6.4

PRESSURE – TEMPERATURE CONVERSION.........................................................................................................................................10

COMPRESSORS ................................................................................................................................................................................................11

7.1

ROTATION...................................................................................................................................................................................................11

7.2

TIMES ...........................................................................................................................................................................................................11

7.3

COMPRESSOR ALARMS............................................................................................................................................................................11

HEATERS...........................................................................................................................................................................................................12

8.1

HEATER ALARMS ......................................................................................................................................................................................12

FREECOOLING.................................................................................................................................................................................................13

9.1

HUMIDITY CONTROL IN FREECOOLING..............................................................................................................................................13

9.2

0-10Volt MODULATING DAMPER............................................................................................................................................................13

9.3

FREECOOLING CONTROLLED BY DIGITAL OUTPUTS ......................................................................................................................13

MANUAL OPERATION OF THE DEVICES....................................................................................................................................................14

AUTOMATIC ROTATION BETWEEN DIFFERENT SHELTER UNITS IN A pLAN...........................................................................................14

11.1

CRITICAL SITUATIONS........................................................................................................................................................................14

11.2

FORCING.................................................................................................................................................................................................14

11.3

FIXED TIME ROTATION.......................................................................................................................................................................14

ALARMS............................................................................................................................................................................................................15

12.1

ALARM RELAY......................................................................................................................................................................................16

12.2

SUMMARY ALARM TABLE.................................................................................................................................................................16

ALARM LOG.....................................................................................................................................................................................................17

13.1

BASIC LOG (pCO1 only if the clock card is installed – pCO2) ..............................................................................................................17

13.2

ADVANCED LOG (pCO2)......................................................................................................................................................................17

LIST OF PARAMETERS AND DEFAULT VALUES......................................................................................................................................21

SCREENS...........................................................................................................................................................................................................25

15.1

LIST OF THE SCREENS.........................................................................................................................................................................25

SUPERVISION...................................................................................................................................................................................................27

16.1

CAREL SUPERVISOR............................................................................................................................................................................27

16.2

BMS..........................................................................................................................................................................................................27

16.3

GSM PROTOCOL....................................................................................................................................................................................27

16.4

GSM VARIABLE DATABASE ..............................................................................................................................................................27

16.5

SUPERVISOR VARIABLE DATABASE...............................................................................................................................................28

ELECTRONIC EXPANSION VALVE..............................................................................................................................................................31

THE USER TERMINAL ....................................................................................................................................................................................32

18.1

EXTERNAL DISPLAY............................................................................................................................................................................32

18.2

BUILT-IN DISPLAY ...............................................................................................................................................................................32

MANAGING THE CONNECTION BETWEEN BOARDS (pLAN).................................................................................................................33

19.1

ASSIGNING THE ADDRESSES.............................................................................................................................................................33

INITIAL INSTALLATION AND UPDATING THE SOFTWARE...................................................................................................................34

20.1

DOWNLOADING THE PROGRAM FROM A HARDWARE KEY......................................................................................................34

20.2

DOWNLOADING THE PROGRAM FROM A COMPUTER................................................................................................................34

20.3

INSTALLING THE DEFAULT PARAMETERS....................................................................................................................................34

20.4

SELECTING THE LANGUAGE.............................................................................................................................................................34

Standard Shelter

Cod. +030221471 – Rel. 2.0 – April 01, 2003

1 GENERAL

1.1 SHELTER

1.2 THE PROGRAM

The “Standard Shelter” program can be used with CAREL pCO1 (xs-small-medium) or pCO2 boards (small-medium), and is used to manage

direct expansion shelter units.

The main functions of the program are:

• management of the temperature and the humidity in technological environments

• management of 1 or 2 hermetic or semi-hermetic compressors

• management of 1 electronic valve for each compressor

• management of 1 or 2 electric heaters

• management of one 0-10V modulating or 3-position freecooling damper

• management of an external humidifier

• management of 2 modulating condenser fans, controlled by pressure or temperature

• outlet temperature control

• alarm management, alarm log, signals

• complete management of the device timers

• connection to local supervision networks and BMS (LonWorks, Bacnet, Modbus)

• send SMS (text) messages to GSM cellular phones in the event of alarms on the unit

• possibility to modify the set point and set point limits by sending SMS (text) messages from a GSM cellular phone

The external or built-in terminal with LCD display can be used to perform the following functions, at any time:

• display the values measured by the probes and calibrate the probes if necessary

• switch the unit on/off

• check and reset the alarms

• program the configuration parameters and the operating parameters with password-protected access

• check the operating hours of the controlled devices with password-protected access

• set the clock

• select one of different languages available (English, Italian, German, French, Spanish)

By connecting to a CAREL pLAN network, the program can also manage the following functions:

• automatic rotation, by time or by alarm, of a maximum of 8 units

• temperature and humidity management on a maximum of 8 units

• use just one external LCD terminal to control a maximum of 8 units

Standard Shelter

Cod. +030221471 – Rel. 2.0 – April 01, 2003

1.3 SETTING UP THE pLAN NETWORK

The following diagram shows the addresses of all the devices that can be controlled using the shelter application.

To set the address of the various devices, refer to the chapter MANAGING THE CONNECTION BETWEEN BOARDS (pLAN)

[driver valvola = valve driver]

Standard Shelter

Cod. +030221471 – Rel. 2.0 – April 01, 2003

2 LIST OF CONFIGURATIONS

The program can manage shelters with pC01 (xs-small-medium) or pCO2 boards (small-medium). When started, the program recognises the

type of board and the size, configuring the inputs and the outputs as a consequence. The following diagrams show the configuration of inputs

and outputs for the possible combinations. For details on the wiring see the technical manual for the pC01 and pCO2 boards.

2.1 DIGITAL INPUTS

HARDWARE NO. FUNCTION

ID 1 Low pressure C1

ID 2 C1 alarm (High press -Thermal cutout comp. - Thermal cutout condenser fan)

ID 3 Thermal cutout alarm heater 1

ID 4 Air flow switch alarm

ID 5 Dirty filter alarm

pCO1 XS/SMALL/MEDIUM

pCO2 SMALL/MEDIUM

ID 6 Blackout alarm

ID 7 Fire-Smoke alarm

pCO1 SMALL/MEDIUM

pCO2 SMALL/MEDIUM

ID 8 Thermal cutout alarm evaporator fan

ID 9 Low pressure C2

ID 10 C2 alarm (High press -Thermal cutout comp. - Thermal cutout condenser fan)

ID 11 Thermal cutout alarm heater 2

ID 12 External alarm

ID 13 ---

pCO1 MEDIUM

pCO2 MEDIUM

ID 14 ---

2.2 ANALOGUE INPUTS

NO. pCO1 XS pCO1 – pCO2 SMALL pCO1 – pCO2 MEDIUM

B 1

Condensing pressure 1/

Condensing temperature 1

Condensing pressure 1/

Condensing temperature 1

Condensing pressure 1/

Condensing temperature 1

B 2 Ambient temperature Ambient humidity

Ambient humidity

B 3 Outside temperature Ambient temperature

Condensing pressure 2

Condensing temperature 2

B 4 Outlet temperature Outside temperature Outside temperature

B 5 Outlet temperature Outlet temperature

B 6 Ambient temperature

B 7 ---

B 8 ---

2.3 DIGITAL OUTPUTS

HARDWARE NO. FUNCTION

DO 1

Outlet fan

DO 2 Compressor 1

DO 3 Heater 1

DO 4 Serious alarm

pCO1 XS/SMALL/MEDIUM

pCO2 SMALL/MEDIUM

DO 5 Minor alarm 1

DO 6

Minor alarm 2

DO 7 Open freecooling

pCO1 SMALL/MEDIUM

pCO2 SMALL/MEDIUM

DO 8 Close freecooling

DO 9 Compressor 2

DO 10 Heater 2

DO 11 Humidifier On/Off

DO 12 ---

pCO1 MEDIUM

pCO2 MEDIUM

DO 13 ---

2.4 ANALOGUE OUTPUTS

HARDWARE NO. FUNCTION

AO 1

Freecooling

AO 2 Outlet fan

pCO1 XS/SMALL/MEDIUM

pCO2 SMALL/MEDIUM

AO 3 Condenser fan 1

pCO1 MEDIUM

pCO2 MEDIUM

AO 4 Condenser fan 2

Standard Shelter

Cod. +030221471 – Rel. 2.0 – April 01, 2003

3 TEMPERATURE CONTROL

The heating and cooling devices are managed based on the temperature measured by the room probe, compared against the temperature set

point.

• Programmable parameters: temperature set point, proportional band (this may be different for heating and cooling), dead zone,

freecooling start and end point as a percentage of the proportional band.

• Fixed parameters: compressor and heater on/off points in the proportional band.

3.1 SHELTER

NB.: All the temperature values indicated in the following graphs refer to the default values

1 COMPRESSOR 1 HEATER

If freecooling is not possible or if

compressor with freecooling = NO

COMP 2

COMP.1

25.0

RES.1+2

21 0

RES 1

If freecooling not possible

50%

1 COMPRESSOR

If freecoolin

33.3%

23.0

RES 1

RES.1+2

RES.2

21.5

22.5

20.5

19.5

Heaters in binary management

33.3% 66.6%

If freecoolin

COMP.2

25.5

COMP.1

33.3%

66.6%

Set temperature

Ambient

tem

erature

100%

Dead Z.

Proportional band cool

Proportional band heat

19.5

3°C

HEATING

COOLING

22.5

23.0

23.5

26.5

Ambient

tem

erature

Ambient

tem

erature

Ambient

tem

erature

Ambient

tem

erature

Ambient

tem

erature

FREECOOLING DAMPER 0-10Volt

20%

FREECOOLING DAMPER 3 POS.

20%

Control with

Digital output 7 and 8

Ambient

tem

erature

Ambient

tem

erature

100%

19.5

100%

23.0

23.5

25.0

24.5

26.5

26.5 23.5

23.5

22.5

Dead Z.

0.5ºC

0.5ºC 3°C

0% 0%

Standard Shelter

Cod. +030221471 – Rel. 2.0 – April 01, 2003

3.2 OTHER TEMPERATURE FUNCTIONS

The high and low temperature alarms generate a signal with an alarm screen, and have a modifiable delay.

NB.: All of the values in the following graphs refer to the default values

The stop dehumidification differential defines the minimum temperature below which the dehumidification function is stopped; the function can

start again if the temperature rises back over the set Start dehumidification offset; the differential and offset can both be modified.

3.3 HUMIDITY CONTROL

The humidification and dehumidification devices are managed based on the humidity values measured by the probe in the room (or at the

intake). This humidity is compared against the humidity set point, and the devices are activated according to the difference. The proportional

band identifies the operating field of the shelter, and can have different values in humidification and dehumidification mode. There is a fixed

dead zone of 0.2% around the set point equal that identifies a zone in which the devices are not activated.

Humidification is only available on medium boards; dehumidification is on the other hand also available for small boards (not available on the

pCOxs, as the humidity probe cannot be installed) and works by activating the compressor/compressors enabled for this function, and by

operating the outlet fan at a certain speed. This speed can be modified, and as default is equal to 50% (5.0V).

Humidification, on medium boards, is managed using a digital output (open/closed).

Dehumidification, on small and medium boards, is managed by controlling the compressor/compressors.

Dehumidification is interrupted if the ambient temperature falls below a certain value. The corresponding differential and offset can be set. In

any case, dehumidification is always possible if: Ambient temperature > Temperature set point – Temperature dead zone.

The 0-10Volt modulating output for the outlet fan in dehumidification mode is automatically reduced by 50% (modifiable);

If the outlet fan is managed by a digital output (open/closed), in dehumidification the outlet fan speed will remain unvaried.

The following diagrams illustrate the behaviour of the humidification and dehumidification devices.

NB.: All of the values in the following graphs refer to the default values

Set tem

erature

Ambient

humidit

(

)

Ambient

humidit

(

)

Set humidity

Proportional band dehumidification

Proportional band humidification

40.0%

10.0%

50.0%

60.0%

Off

40.0%

50.0%

60.0%

ON-OFF SWITCH

1/2 COMPRESSORS

HUMIDIFICATION

DEHUMIDIFICATION

Ambient

Tem

erat.

(

ºC

)

17.5ºC

Dead Z.

Dehumid. Temperature differential limit

Dehumid. Temperature offset limit

5.0

4.0ºC

Off

21.5ºC

DEHUMIDIFICATION ENABLE

Off

Ambient

tem

erature °C

COOL

Set tem

erature 23.0°C

Heat band

Low temperature alarm

10°C

HEAT

13.0 19.5

23.5

26.5

33.0

3°C

High temperature alarm

10°C

Cool band

22.5

Standard Shelter

Cod. +030221471 – Rel. 2.0 – April 01, 2003

3.4 OTHER HUMIDITY FUNCTIONS

The high and low humidity alarms generate a signal with an alarm screen.

The delay can be modified.

4 OUTLET LIMITATION

This function prevents the introduction of air that is too cold. A temperature probe must be installed on the shelter outlet, and both the probe and

the function must be enabled, by setting the following parameters: Outlet limit set point and Outlet differential; these define a limitation zone, as

represented in the following diagrams.

The outlet limitation function acts on the proportional cooling request. The effect on the devices is therefore the same as when the room

temperature decreases, that is, progressively stopping the devices (see the paragraph on “Temperature control”).

NB.: All of the values in the following graphs refer to the default values

Outlet Limit

NO LIMIATION

TOTAL LIMITATION

8°C

12°C

Outlet Differential

Limitation of

request

100%

4°C

If we consider that the room temperature, and therefore the proportional request, remain constant, a graph can be defined that shows the

effective request in the various operating conditions:

Effective

uest

Outlet

temperature

8°C 9°C 10°C 11°C

100%

50%

75%

25%

12°C

Outlet

Limit

100%

75%

50%

25%

With constant room

tem

erature

26.5°C

25.7°C

25°C

24.2°C

23.5°C

Outlet differential

As can be seen, if the outlet temperature is between the outlet set point and the outlet differential, the cooling devices are increasingly limited as

the temperature lowers.

The limitation function works differently in dehumidification mode, where the modulation zone is ignored, as illustrated in the following diagram:

Humid. Set

30.0%

Humid. Diff. Dehum. Diff.

Low humidity alarm

10.0%

20.0%

Ambient

humidit

(

)

10.0%

HUMIDIF.

DEUHMID.

30.0%

80.0%

High humidity alarm

Outlet temp.

(

°C

)

OFF

Outlet differential

Outlet limit

8.0

4.0°C

DEHUMID.

POSSIBLE

DEHUMID.

OFF

OUTLET LIMITATION

Standard Shelter

Cod. +030221471 – Rel. 2.0 – April 01, 2003

5 OUTLET FAN

The outlet fan is always on when the unit is ON. It can be managed using an On–Off or modulating output. There are two alarms relating to the

fan, thermal cutout and air flow switch, which automatically switch the unit OFF; both the alarms require manual reset.

5.1.1 On-Off management

The outlet fan will start, after a set delay (default 10 sec), when the shelter unit starts. It will stay on until the unit is switched off. A stop delay

time for the fan after the unit has been switched off can also be set (default 20 sec).

In the event of a blackout, the outlet fan continues to operate, so as to ensure the recirculation of air inside the technological environment. In this

phase the freecooling function can also be modulated if the conditions are suitable.

5.1.2 Modulating management

NB.: All of the values in the following graphs refer to the default values

The minimum and maximum speed of the fan can be set. The default values 5.0V and 10.0V.

It should be noted that in dehumidification mode the speed is automatically reduced to the minimum value, 5.0V (50%); this value can be

modified if necessary.

In the event of a blackout the outlet fan continues to operate at 100% speed, so as to ensure the constant recirculation of air inside the

technological environment. In this phase the freecooling function can also be modulated if the conditions are suitable.

6 CONDENSER FANS

The condenser fans are controlled based on the condensing pressure and the status of the compressors. The fans are managed using 0-10V

modulating outputs. The control function uses the Condensing pressure set point and Differential, as shown below:

NB.: All of the values in the following graphs refer to the default values

Prevent

differential

Condensing set

Condensing

differential

14.0

16.0

18.0

20.0

HP differential

23.5

24.5

HP PREVENT

HP ALARM

Compressor

status

Condensino

pressure (bar)

Fan status

Ambient

tem

(

°C

)

COOLING

HEATING

100%

100% 0%

Proportional band cool

Proportional band heat

Set temperature

19.5

100%

3°C

Minimum speed (5.0V)

Maximum speed (10.0V)

Fan speed

100%

50%

0.5°C 0.5°C 3°C

22.5 23.0

23.5 26.5

Standard Shelter

Cod. +030221471 – Rel. 2.0 – April 01, 2003

Representation of the modulating output:

The maximum and minimum speed of the condenser fans can be set; if the minimum speed set is greater than 0V, the fan will be able to operate

at the minimum speed down to 1.0 bar below the condensing pressure set point before stopping altogether (see the dashed part in the graph

above).

6.1 NUMBER OF PROBES AND CONDENSING COILS

Note: the activation of the fans always depends on the status of the compressors, as well as the values read by the probes.

1 Coil 2 Coils

1 Compressor 2 compressors 1 Compressor 2 compressors

1 Fan 2 Fans 1 Fan 2 Fans 1 Fan 2 Fans 1 Fan 2 Fans

0 probes The fans work together when any of the compressors starts

Each fan starts together with the corresponding

compressor

1 Probe

The probe directly

controls the fan. If the

probe is faulty the fan

will be activated

together with the

compressor

The probe controls

both fans. If the probe

is faulty the fans will be

activated together with

the compressor

The probe directly

controls the fan. If the

probe is faulty the fan

will be activated

together with the

compressors

The probe controls

both fans. If the probe

is faulty the fans will be

activated together with

the compressors

Not possible Not possible Not possible Not possible

2 Probes

Not possible Not possible

The fan works based

on the greater of the 2

pressure values. If both

probes are faulty the

fan will be activated

together with the

compressors. If only

one probe is faulty the

fan works based on the

value of the other

probe.

The fans work based

on the greater of the 2

pressure values. If both

probes are faulty the

fans will be activated

together with the

compressors. If only

one probe is faulty the

fans work based on the

value of the other

probe

Not possible Not possible Not possible

The fans work

based on the

pressure of the

corresponding

circuit. If one of

the probes is

faulty, the fan will

be activated

when of the

compressor in the

same circuit

starts.

If no condenser probe is enabled, the fans will start when the corresponding compressor starts, if there are 2 coils. With just one coil, on the

other hand, the fans will always work together when either of the 2 compressors starts. In this case, they will start at 100% speed.

6.2 PREVENT FUNCTION

This prevents the high pressure alarm when the compressors are off. Normally the condenser fans only start when the compressors are on, but in

this case they are forced on so as to lower the pressure and attempt to prevent the high pressure alarm, which would stop the unit. There is no

modulation in this phase, and the fans are started immediately at 100% speed.

6.3 SPEED-UP FUNCTION

To overcome the inertia when starting high-power modulating fans, they can be forced on for a few seconds at maximum speed, after which the

speed is modulated based on the condensing pressure.

6.4 PRESSURE – TEMPERATURE CONVERSION

Either pressure probes or temperature probes can be used. When using pressure probes, the screens in the I/O branch show the temperature

corresponding to the pressure value for each probe, keeping account of the type of refrigerant used, selected by a parameter in the manufacturer

branch.

Max. speed (100%)

Min. speed (0%)

Condensing

ressure

(

bar

)

Condensing differential

13.0

2.0 bar

0% 14.0

16.0

Standard Shelter

Cod. +030221471 – Rel. 2.0 – April 01, 2003

7 COMPRESSORS

The compressors are managed as simple ON-OFF loads (see TEMPERATURE CONTROL). The maximum number of compressors is 2.

7.1 ROTATION

The operation of the compressors can be rotated following FIFO logic (first in, first out). This helps balance the operating hours between the

compressors.

7.2 TIMES

A number of safety times are used to protect the compressors:

• minimum on time;

• minimum off time;

• minimum time between starts of the same compressor;

• minimum time between starts of different compressors.

7.3 COMPRESSOR ALARMS

From digital inputs:

Generic compressor alarm, including: High pressure / Compressor thermal cutout / Condenser fan thermal cutout;

- Low pressure.

If one of the alarm inputs is not used, it should be closed electrically on the 24Vac power supply.

For details on the electrical connections of the alarm inputs see the technical manual for the pC01– pCO2 boards.

From analogue input:

- High pressure alarm from pressure transducer.

7.3.1 GENERIC ALARM: High pressure / Compressor thermal cutout / Condenser fan thermal cutout

Immediate alarm generated by an external pressure switch or by a thermal cutout; the digital input switches from closed to open and the

compressor is immediately stopped. Reset is manual, that is, the user must press the Alarm button on the terminal to be able to restart the

compressor, as long as the pressure switch or the thermal cutout have been reset and the digital input is closed. After the compressor is stopped,

the safety times are counted so that following the reset of the alarm the compressor can not be restarted immediately.

7.3.2 LOW PRESSURE

Alarm generated by an external pressure switch.

This alarm is ignored for a time that can be set on the screen, from when the compressor starts, to allow time for the pressure in the circuit to

stabilise. If at the end of the time the contact is still open, the compressor stops and an alarm is signalled. If the contact closes before the time

has elapsed, the alarm is not signalled and the timer is reset.

Reset is manual, that is, the user must press the Alarm button on the terminal to be able to restart the compressor, as long as the pressure switch

has been reset and the digital input is closed. After the compressor is stopped, the safety times are counted so that following the reset of the

alarm the compressor can not be restarted immediately.

7.3.3 HIGH PRESSURE FROM HIGH PRESSURE TRANSDUCER

Immediate alarm generated by the measurement of excessive pressure in the circuit. The set point and differential for the high pressure alarm

can be set. Each probe can generate a high pressure alarm that stops the compressor in the corresponding circuit.

If the shelter features 2 compressors but only the probe corresponding to the first circuit is enabled, the high pressure alarm detected by the latter

will stop both compressors. In this case, the high pressure alarm will relate to both the first and second circuit.

Reset is manual, that is, the user must press the Alarm button on the terminal to be able to restart the compressor, as long as the pressure has

fallen below the set point – differential. After the compressor is stopped, the safety times are counted so that following the reset of the alarm the

compressor can not be restarted immediately.

NB.: All the values in the following graph refer to the default values

Pressure

(

bar

)

HIGH PRESSURE ALARM

High press.

threshold

High pressure

differential

23.5bar

1.0bar

Standard Shelter

Cod. +030221471 – Rel. 2.0 – April 01, 2003

8 HEATERS

The heaters are managed as simple ON-OFF loads. Normally up to 2 heaters with the same power can be managed, connected to the 2 outputs.

“Binary management” allows the use of three heating steps with just two outputs. Consequently, there are two possible options:

• management of 2 loads with different power values;

• management of 3 loads. To use this system, a recognizer is required (NOT supplied), which, connected to the outputs, reads the logic

and activates the loads.

The outputs behave as follows:

CODE 2 DIFFERENT LOADS 3 LOADS

STEP 1 Relay 1=On Relay 2=Off 10 Heat.1=On / Heat.2=Off Heat.1=On / Heat.2=Off / Heat.3=Off

STEP 2 Relay 1=Off Relay 2=On 01 Heat.1=Off / Heat.2=On Heat.1=On / Heat.2=On / Heat.3=Off

STEP 3 Relay 1=On Relay 2=On 11 Heat.1=On / Heat.2=On Heat.1=On / Heat.2=On / Heat.3=On

The outputs are activated with a slight delay from one to the other, to avoid simultaneous peaks.

8.1 HEATER ALARMS

Each heater features a digital input to be connected to a thermal cutout or circuit breaker for signalling any anomalies.

If one of the inputs is not used, it must be closed electrically on the 24Vac power supply.

The alarm is immediate and is generated when the digital input switches from closed to open; the heater is immediately switched off. Reset is

manual, that is, the user must press the Alarm button on the terminal to be able to restart the heaters, as long as the thermal cutout - circuit

breaker has been reset by closing the digital input.

Standard Shelter

Cod. +030221471 – Rel. 2.0 – April 01, 2003

9 FREECOOLING

Energy savings can be achieved using outside air as a means of cooling the environment being air-conditioned. This is done using a damper to

let in outside air that is colder than the air inside the environment.

It must be established whether the temperature of the outside air is sufficiently below the ambient temperature so as to enable freecooling. The

difference must be less than or equal to a certain value, defined as the Freecooling offset.

The freecooling function is modulated according to the ambient temperature.

The freecooling option can be set to operate at the same time as the compressors, or alternatively not. If opting for separate operation, when the

compressor starts the freecooling damper closes.

The freecooling request decreases proportionally to the lowering of the air outlet temperature (see OUTLET LIMITATION)

If the freecooling function is not enabled, due to one of the above causes, the damper can still remain minimally open, at a level set by the user.

The freecooling damper is closed completely only in the following cases:

- When the shelter is off

- Outside temperature probe faulty, not connected or not enabled

- Room temperature probe faulty or not connected

- Fire/Smoke alarm

The freecooling function can be controlled in two different ways:

• Using a 0-10V modulating output on the pCO1-pCO2

• Using two digital outputs (not available on pCO1xs)

See TEMPERATURE CONTROL.

In the event of blackouts, the freecooling function continues to operate, thus continuing, if possible, the inlet of air that is colder than the

ambient temperature. During this phase the normal freecooling offset (default value 2.0ºC) is no longer considered, but rather a new fixed offset

of 1.0ºC is used. In this phase the outlet fan also operates at 100% speed.

Even if the compressor/compressors cannot operate due to alarms, the normal freecooling offset (default value 2.0ºC) is no longer considered,

but rather the fixed offset of 1.0ºC is used.

The humidity in the room is also controlled.

9.1 HUMIDITY CONTROL IN FREECOOLING

NB.: All the values in the following graph refer to the default values

If the ambient humidity is too high, the freecooling function will be disabled for a certain time that can be set by the manufacturer. Once this

time has elapsed, if the humidity has fallen below the freecooling re-enabling threshold, the damper will be able to modulate normally again.

During a blackout this function is disabled.

9.2 0-10Volt MODULATING DAMPER

Dampers that use a 0-10Volt modulating signal from the pCO1-pCO2 to vary their degree of opening from 0% to 100%. The 0-10Volt electrical

signal is directly proportional to the proportional temperature band, therefore the degree of opening always corresponds to demand.

9.3 FREECOOLING CONTROLLED BY DIGITAL OUTPUTS

Based on the activation time of the relays, the degree of opening of the damper varies from 0% to 100%, using a travel time called the “running

time” (time required to open or close completely, a rated value for the valves). The degree of opening of the damper is calculated based on the

proportion between the temperature differential and the running time.

9.3.1 REALIGNMENT

As can be imagined, the control of the damper using this system is quite difficult for the program to manage, as there is no feedback on the exact

position of the damper. The following solutions are used to overcome this problem:

• whenever the temperature control functions require the complete opening or closing of the damper, the program increases the

activation time of the opening or closing relays by 25% to ensure the complete closing / opening.

• whenever the board is switched on, the damper is closed completely for the running time, after which modulating operation can begin

based on the actual request.

Ambient

Humidit

FREECOOLING ENABLING

Enabled

Disabled

0 70.0

Standard Shelter

Cod. +030221471 – Rel. 2.0 – April 01, 2003

10 MANUAL OPERATION OF THE DEVICES

The devices connected to the outputs can be activated manually, bypassing the safety times, the compressor rotation and independently of the

control functions and the values measured by the probes. The only support in manual mode involves the alarms, so as to ensure safety and

protect the devices. The activation of the analogue outputs in manual mode sets a value between 0V and 10V. The manual procedure can only

be used if the unit has been switched off using the button, and ends automatically 30 minutes after the manual activation of the last device.

During the manual operation of the devices, the shelter cannot be switched on. This operating mode is identified by the message “Manual

procedure” on the last row of the display, on the main Menu screen. The parameters for the manual operation of the devices are accessed in the

Maintenance branch of screens, with password protection.

11 AUTOMATIC ROTATION BETWEEN DIFFERENT SHELTER UNITS IN A pLAN

The boards connected in a pLAN network have the advantage of being able to be managed directly by the program in certain “critical

situations”, that is, if anomalies occur (alarms, blackouts…), or alternatively due to the “Rotation” and “Forcing” functions.

The program operates as defined by a number of parameters:

• connection class of the boards: Not present, Present / No Rotation, Present / Rotation. This parameter must be set on each master board. Description:

- Not present: the unit is not connected to the pLAN network;

- Present / No Rotation: the unit is physically connected to the pLAN network but is excluded from the rotation function (it can in any case

manage the unit in standby, the shared terminal and the print function);

- Present / Rotation: the unit also takes part in the Rotation function.

• Unit in Standby: In a pLAN network, one of the units in Present / Rotation mode may be in standby. When started using the button, this

unit enters Standby mode (that is, off, awaiting activation). Clearly, if there is only one unit in the network, this cannot be in standby.

IMPORTANT. The functions described below are not possible unless:

• There are at least two units selected in Present / Rotation mode

• One unit is in Standby

The functions are managed by the board with pLAN address 1; if this is disconnected from the pLAN network or is switched off due to a

blackout, the board in Standby is activated and the functions in question will be suspended until unit 1 is reset. Conversely, switching unit 1 off

using the On-off button does not interrupt the network functions.

11.1 CRITICAL SITUATIONS

The unit in Present / Rotation mode that is in Standby is activated in one of the following critical situations on the active boards:

• one of the boards is disconnected from the pLAN network

• one of the boards is switched off using the button

• one of the boards is switched off due to a serious alarm (see the alarm table)

When one of the units in critical situation is reset, this is started again and the spare unit returns to Standby mode.

If a critical situation occurs on the Standby unit, there is no action at a pLAN level, except for the alarm signal on the unit in question.

11.2 FORCING

The unit in Present / Rotation mode that is in Standby is activated automatically in the event where one of the other units cannot manage to

satisfy the heating or cooling request. Therefore, if the temperature increases such as to cause an excessive load on the active units, after a

certain time the required number of units in standby will be activated. Each unit in this situation can bring about the activation of the units in

standby. The parameters that need to be set for the forcing function are the Differential, Offset and Delay, which are different for heating and

cooling. The diagram below illustrates the function:

NB.: All the values in the following graph refer to the default values

11.3 FIXED TIME ROTATION

Fixed time rotation is based on a parameter that establishes the interval between rotations. The minimum time that can be set is 0h, and in this case

automatic rotation is activated every each 5 minutes. The maximum time is 240h (10 days). The time starts counting when the board with pLAN address

1 is started, and indeed this board manages the rotation functions. Rotation occurs following the order of pLAN addresses.

Rotation will be reset automatically whenever a unit is added to or removed from the rotation function by modifying the connection class (see above).

15.0

Ambient

tem

(

°C

)

RAFFR

RISCALD

Set tem

erature

Heat band

Heating forcing differential

3°C

Offset in heating

Offset in cooling

Forcing delay in

heating

Forcing delay in

cooling

8.0ºC

3°C

Cool band

19.0

16.5

23.0

26.5

27.0 31.0

Cooling forcing differential

Standard Shelter

Cod. +030221471 – Rel. 2.0 – April 01, 2003

12 ALARMS

The alarms managed by the program are designed to protect the connected devices and provide signals if the control parameters are outside of

the range of normal values or if there are faults on the board. The alarms may derive from the alarm digital inputs, from the probes or from the

board. The effect of the alarms ranges from signal-only, to the shutting down of one or more devices, to the shutting down (Off) of the shelter.

Many alarms feature modifiable delays.

When an alarm goes off, the following actions occur:

• the buzzer on the external terminal sounds (not featured on the built-in terminal)

• the red LED under the ALARM button comes on

• the message AL flashes on the Menu screen

Pressing the Alarm button mutes the buzzer and displays the alarm screen. If there is more than one active alarm, once having entered the alarm

menu, simply use the arrow buttons to scroll the alarms. Pressing any other button exits the alarm screen, however the events remain saved and

are displayed again whenever the Alarm button is pressed.

To manually reset the alarms and delete the messages, simply enter the alarm screen and press the Alarm button again; if the cause of the alarms

is no longer present (digital inputs reset or temperature returned to normal, etc…) the screen disappears, the red LED goes off and the message

NO ACTIVE ALARMS is displayed. If the causes of one or more than one alarm are still present, only the alarms whose causes are no longer

present are reset, while the others remain displayed and the buzzer and the red LED come on again.

All the alarms require manual reset.

Therefore, to reset the alarms the operator must act directly on the terminal.

The alarms may be: Serious, Minor 1, Minor 2 (not present on the pCO1xs).

The type is selected on the terminal by the operator.

Standard Shelter

Cod. +030221471 – Rel. 2.0 – April 01, 2003

12.1 ALARM RELAY

Each alarm managed can be selected as Serious or Minor type 1 or 2 (not present on the pCO1xs), thus defining which relays are activated. The

delay before closing can be set for all 3 relays.

12.2 SUMMARY ALARM TABLE

CODE DESCRIPTION DELAY UNIT OFF DEVICES OFF

AL01

Generic compressor alarm 1

(

High press -Thermal cutout

comp. - Thermal cutout condens. fan)

- -

Compressor 1 and Condenser

fan 1

AL02

Generic compressor alarm 2 (High press -Thermal cutout

comp. - Thermal cutout condens. fan)

- -

Compressor 2 and Condenser

fan 2

AL03 Low pressure compressor 1 See screen T2 -

Compressor 1 and Condenser

fan 1

AL04 Low pressure compressor 2 See screen T2 -

Compressor 2 and Condenser

fan 2

AL05 No air flow See screen T4 yes All

AL06 Outlet fan cutout - yes All

AL07 Thermal cutout heater 1 - - Heater 1

AL08 Thermal cutout heater 2 - - Heater 2

AL09 Fire / Smoke alarm - yes All

AL10 Filters dirty See screen T4 - -

AL11 High ambient temperature See screen T2 - -

AL12 Low ambient temperature See screen T2 - -

AL13 High ambient humidity See screen T2 - -

AL14 Low ambient humidity See screen T2 - -

AL15 Operating hour threshold reached, compressor 1 - - -

AL16 Operating hour threshold reached, compressor 2 - - -

AL17 Operating hour threshold reached, outlet fan - - -

AL18 Room temperature probe faulty or disconnected 60 secs (fixed) - -

AL19 Outside air temperature probe faulty or disconnected 60 secs (fixed) - -

AL20 Outlet air temperature probe faulty or disconnected 60 secs (fixed) - -

AL21 Room humidity probe faulty or disconnected 60 secs (fixed) - -

AL22 Condenser 1 pressure probe faulty or disconnected 60 secs (fixed) - -

AL23 Condenser 2 pressure probe faulty or disconnected 60 secs (fixed) - -

AL24 Condenser 1 temperature probe faulty or disconnected 60 secs (fixed) - -

AL25 Condenser 2 temperature probe faulty or disconnected 60 secs (fixed) - -

AL26 Blackout - -

All except for outlet fan and

freecooling

AL27 Clock card absent or not working - - -

AL28 High pressure circuit 1 (from probe) - -

Compressor 1 and Condenser

fan 1

AL29 High pressure circuit 2 (from probe) - -

Compressor 2 and Condenser

fan 2

AL30 Auxiliary alarm - - -

AL31 Operating hour threshold reached, humidifier - - -

AL32 pLAN alarms

AL33 Driver 1 alarm, probes faulty or disconnected - - Compressor 1

AL34 Driver 1 EEPROM faulty or damaged - - Compressor 1

AL35 Driver 1 valve motor faulty or damaged - - Compressor 1

AL36 Driver 1 alarm, battery discharged or faulty - - -

AL37 Driver 1 high evaporation pressure (MOP) See Fj - -

AL38 Driver 1 low evaporation pressure (LOP) See Fj - -

AL39 Driver 1 low superheating See Fi - Compressor 1

AL40 Driver 1 high suction pressure See Fi - -

AL41 Driver 1 valve not closed during blackout - - Compressor 1

AL42 Driver 2 alarm, probes faulty or disconnected - - Compressor 2

AL43 Driver 2 EEPROM faulty or damaged - - Compressor 2

AL44 Driver 2 valve motor faulty or damaged - - Compressor 2

AL45 Driver 2 alarm, battery discharged or faulty - - -

AL46 Driver 2 high evaporation pressure (MOP) See Fj - -

AL47 Driver 2 low evaporation pressure (LOP) See Fj - -

AL48 Driver 2 low superheating See Fi - Compressor 2

AL49 Driver 2 high suction pressure See Fi - -

AL50 Driver 2 valve not closed during blackout - - Compressor 2

AL51 Driver 1 pLAN alarm: not connected to the corresponding unit 60 sec (fixed) - Compressor 1

AL52 Driver 2 pLAN alarm: not connected to the corresponding unit 60 sec (fixed) - Compressor 2

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Carel pCO2 SMALL User manual

Brand: Carel

Model: pCO2 SMALL

Type: User manual

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